Injections have heretofore been classified roughly into 2 types: a type in which a drug solution is charged into an ampule or vial to provide it, and then transferred from the ampule or vial to a syringe body on its use to inject it into a patient or the like, and another type in which a drug is charged into a vial in the form of powder or lyophilized amorphous powder, and then dissolved again so as to transfer it to a syringe body for its use and to inject it. These injections however have involved problems: i) prolonged time required for the transfer of drug solution, ii). complicated operation, iii) possibility of misoperation and iv) potential problem that glass powder may be mixed into the injections when ampules made of glass are used. In addition, since these injections must be transferred to syringe bodies for their use, they also pose v) a problem of bacterial contamination, the mixing of foreign matter, or the like when no longer sterile.
In order to solve these problems, small volumes of glass or plastic syringe bodies, in which a drug solution was charged in advance, have been investigated in recent years. In the plastic syringe bodies used conventionally, polypropylene resins with a sorbitol nucleating agent added thereto have been used in most of their resin materials. Therefore, they involve a problem that when a drug solution remains charged into such a syringe body for a long period of time, additives, decomposition products thereof and the like are dissolved out of the resin components.
In addition to the syringe bodies charged with a drug solution in advance, containers for infusions and containers for storing medicinal solutions such as a solution for injections, which are injected into the human body, for a long period of time involve a potential problem that since the drug solution comes into contact with a resin constituting such a container for a long time, additives for the resin may be dissolved out into the drug solution. Therefore, a thorough investigation has been required from the viewpoint of safety (the Japanese Pharmacopoeia, Testing Methods of Plastic Containers for Aqueous infusions, Dissolution Test, etc., Manual for the Japanese Pharmacopoeia, B-431). However, fully satisfactory results have not been yet obtained.
On the other hand, these syringe bodies and containers are required to have good transparency from the viewpoint of necessity of observing the turbidity of a drug solution charged therein by the naked eye and determining the amount of the drug which has been administered.
Accordingly, it is an object of this invention to provide a preparation comprising a syringe body or container and a drug solution charged into the syringe body or container, said syringe body or container maintaining its good transparency and being free from the dissolution of additives for a resin constituting the syringe body or container even when storing the drug solution for a long period of time, and moreover to provide a syringe body or container suitable for use in the production of such a preparation.
In view of the foregoing circumstances, the present inventors have carried out an extensive investigation. As a result, it has been found that when a drug solution is charged into a syringe body or container obtained by using a polypropylene resin containing, as a nucleating agent, a phosphoric ester represented by a general formula (1), which will be described subsequently, to mold it, a preparation which is free from the dissolution of additives for the resin and maintains the good transparency of the syringe body or container over a long period of time can be obtained, leading to completion of this invention.